Making games, should I animate in Blender or Unity?
So, let me preface by saying, its been a hot minute since I worked with Unity, and they do update things, so some things might be different.
Unity has really good documentation so id recommend checking that out. https://docs.unity3d.com/Manual/index.html
Unity Learn has tutorials that will get you started and show you how to set up your file structure efficiently. https://learn.unity.com/
Last time I used unity, it had pretty good support for blender, you could choose to import .fbx or just straight up .blend files.
I always animated in blender because I was most comfortable with it, but you can animate in unity as well, I think they had some kind of implementation for that, and I know for sure people have done procedural animations in unity. Here's a really cool GDC talk on procedural animation in unity https://youtu.be/LNidsMesxSE
Rigging can be done &quot;generic&quot; or with Mecanim. Generic is for anything non humanoid, Mecanim, is of course for humanoids, so you need to set up your rig with all the bones Mecanim needs.
https://docs.unity3d.com/Manual/MecanimFAQ.html
You'll want to make sure your walk cycles loop of course, but there's two different ways to approach actual movement. The first is the traditional way, you animate your character looping through their walk/run cycle without actually moving, as though they were on a treadmill. Then you code in their movement and tie the animation to it through an animation controller. The second way is to actually animate your root, so your character changes positions, and then unity has an option to use that root motion as actual character motion. I was never personally able to get this one to work quite right, but the character controller that comes with unity uses it, and handles very nice. The tradeoff between the two is basically greater control and being able to adjust things later, vs (if you animate it correctly) very accurate movement to step ratio.
I would recommend making some very basic stuff in unity before you spend a lot of time on a character and animations. A lot of people try to jump in and make a big RPG like skyrim or something, and then get frustrated and a little angry when they've made all these characters and weapons and armors, and cant figure out how to get all the gameplay actually working.
Anyways, I hope that was helpful, I wish you the best!